Both individuals and organizations are highly dependent on communication networks. The telephone system, automated bank tellers, airline reservation systems, and office information handling systems are examples of communication networks that affect each of our lives on a daily basis. The usefulness of such networks is directly related to their availability, on a moment's notice, for the reliable communication of information.
A single communication network typically includes a variety of transmission media that require both the analog and digital modulation of information. Maintaining the availability of a communication network, accordingly, requires a wide variety of electronic test equipment, and trained technicians with a broad scope of electronic skills. In particular, maintenance of modern communication networks requires equipment and personnel capable of performing protocol testing, digital transmission testing, signalling and supervision testing, and analog transmission testing.
The T-1 transmission line is the most widely employed transmission link used to connect the various nodes and terminals of integrated voice/data communication networks. The capability to test and diagnose T-1 carrier facilities is therefore a required element of a comprehensive testing program for most voice/data communication networks.
Test equipment for monitoring individual characteristics of communication networks are known. For example, Bit Error Rate (BERT) and Block Error Rate (BLERT) testers are commercially available, as are analog test sets. Sophisticated devices such as the 6640/6640D Network Probe.TM. test set, manufactured by Network Communications Corporation, 10120 West 76th Street, Eden Prairie, Minn., are based upon microcomputer technology and provide the capability for complete network testing within a single package.
None of the available communication network test equipment, however, has combined, in a single, compact, and portable piece of test equipment, the capability of performing a full range of T-1 tests in combination with the capability of performing non-T-1 protocol testing, digital transmission, signalling and supervision testing, and analog transmission testing. Moreover, none of the existing test equipment has successfully incorporated a full range of hardware and protocol interfaces (such as RS-232, RS-422, V.35, ISDN, etc.) into a single, compact unit. None of the available portable equipment has had the speed to perform full duplex drop and insert on a T-1 line. Finally, none of the available equipment has incorporated a dual channel oscilloscope, a required piece of equipment for analyzing analog performance characteristics, into the same display used for non-analog output display.
A truly portable, battery operated piece of test equipment for analyzing communication networks that was adaptable to a wide variety of equipment interfaces, that had the speed and capability for performing a full range of T-1 line testing (including full duplex drop and insert), that incorporated a full range of analog testing capability (including a dual channel oscilloscope) and that included a full range of non-T-1 digital transmission, signalling and supervision, and protocol testing capabilities into a portable integrated unit, would be a decided improvement over existing test equipment.